Floor sanding apparatus



June 16, 1964 w. J. GRIFFITH, JR 3,137,106

FLOOR SANDING APPARATUS Filed Nov. 8, 1962 2 Sheets-Sheet 1 lllllh illllii? Wm I\\\\\\\\\\\\\\\\\\MZ/ IL.

Z mg \\\\\\\\\\\\\\\\\\\v INVENTOR. WILLIAM J. GRIFFITH JR.

BY Gama/6Z6 K741142127 iflmdzm/ June 16, 1964 w. J. GRIFFITH, JR

FLOOR SANDING APPARATUS 2 Sheets-Sheet 2 Filed NOV. 8, 1962 INVENTOR. WILLIAM J. GRIFFITH JR.

BY (Mama/6Z6,

United States Patent 3,137,106 FLOOR SANDING APPARATUS William J.. Griffith, In, Norwood Park Township, Cook County, Ill., assignor of one-half to Clarence J. Pruss, Chicago, Ill. Filed Nov. 8, 1962, Ser. No. 236,200

Claims. (Cl. 51176) for simply and eificiently adjusting the endwise position of an arbor in an arbor housing of a floor sanding machine carrying at each end a sanding drum with the arbor having fast thereon a driven bevel gear in meshing engagement with a drive bevel gear projecting into the arbor housing and carried at its lower end by a vertically extending shaft driven by a motor; to mount the arbor in antifriction bearings located in bearing openings at the ends of the arbor housing, each bearing having an outer race held in fixed position in its bearing opening and an inner race with respect to which thearbor is endwise adjustable to vary the degree of meshing engagement between the teeth of the bevel gears to the end that proper driving engagement is provided with a minimum of noise incident thereto; to provide an annular flange fast on and spaced from each end of the arbor against which a sanding drum can be secured with the diameter of each flange and of each outer bearing race and of the driven bevel gear being such that the assembly on the arbor can be inserted through the bearing openings in the arbor housing; to provide the endwise adjustment of the arbor by forming one or more lengthwise extending slots in its periphery underneath an extension of each inner race and threading a set screw or set screws through each extension with the inner end or ends engaging the bottom or bottoms of the slot or slots in the endwise adjusted position of the arbor to hold it against endwise movement.

. In the drawings:

FIG. 1 is a perspective view of floor sanding apparatus in which the present invention is embodied.

FIG. 2 is a view, partly in side elevation and partly in section and at an enlarged scale, of the arbor housing and a portion of the platform of the apparatus shown in FIG. 2, a part of the arbor housing being broken away in order to show the internal details of construction.

FIG. 3 is a top plan view of the arbor housing with the drive shaft being shown in section and showing by broken lines the outlines of the floor sanding drums.

. FIG. 4 is a cross sectional view, at an enlarged scale, taken generally along the line 4--4 of FIG. 3 and showing a portion of the arbor housing and the arrangement of the meshing bevel gears.

Referring now particularly to FIG. 1 of the drawings, it will be observed that the reference character Iii-designates, generally, a floor sanding apparatus of the general type and character shown in the patent above referred to. It includes two sanding drums 1111 which are power driven and are rotatably mounted at the ends of an arbor housing 12 which depends from a platform 13 on which a motor housing 14 is mounted. An upwardly extending handle 15 provided with hand holds 16-16 permits manual direction of the floor sanding apparatus 10. A

conductor cable 17 serves to connect the floor sanding apparatus for energization to a suitable source of electric power. The cable 17 extends through and is held by handle 15 is a dust bag 20 which is connected to the vacuum system (not shown) of the floor sanding apparatus 10.

The floor sanding drums 1111 are driven by an electric motor that is shown by broken lines at 24 within the motor housing 14. The motor 24 is arranged to rotate a drive shaft 25 which extends downwardly through the motor housing 14 and is provided at its lower end with a drive bevel gear 26. As shown more clearly in FIGS. 2, 3 and 4 the drive bevel gear 26 meshes with the teeth of a driven bevel gear 27 which is mounted on a horizontally extending arbor 28. It will be understood that the bevel gears 26 and 27 are suitably secured to the shaft 25 and arbor 28 respectively. For example, they may have a press fit and inaddition can be secured against rotation by socket set screws (not shown).

The arbor 28 extends through bearing openings 29 at the ends of the arbor housing 12. One of these bearing openings is shown in FIGS. 2 and 4 and their diameter is indicated at 319. The maximum diameter of the driven bevel gear 27 is indicated at 31 in FIG. 4 and it will be observed that this is slightly less than the diameter 30 of the openings 22. As will appear hereinafter, this arrangement permits assembling the driven bevel gear 27 on the arbor 28 and then the insertionof the assembly through the bearing openings 29 into the arbor housing 12. The arbor 28 is rotatably mounted at the ends of the arbor housing 12 by antifriction bearing assemblies 32 32. They are of identical construction and the description of one applies to both. The details are shown more clearly in FIG. 4. Here it will be observed that the bearing assembly 32 includes an outer race 33 the outer diameter of which is such that it can be readily inserted into the bearing opening 29 where it is held in place, in part, by socket set screws 34. It will be understood that two socket set screws 34 are employed but only one is shown in FIG. 4. Endwise movement of the outer race 33 toward the arbor housing 12 is prevented by a split snap ring 35 which can be inserted in its annular slot after the bearing assembly 32 has been positioned in the bearing opening 29. Antifriction means in the form of ball bearings 36 are interposed between the outer race 33 and an inner race 37 which is adjustable along the arbor 28 and is provided with an extension 38 through which two socket set screws 39 are threaded, only one being shown. The extension 38 projects over an elongated slot 40 the bottom surface of which is indicated at 41. Preferably two elongated slots 40 are provided each being individualto a socket set screw 39. It will be understood that similar elongated slots 40 are provided near the other end of the arbor 28 for receiving the socket set screws 39 of the other antifriction bearing assembly 32. It will be observed that there is a fixed distance, as indicated at 42, between the ends ofthe arbor housing 12 and that the split snap rings 35 bear against the same to position the outer races 33 in fixed relation thereto. Because of the necessary manufacturing tolerances it is essential that some means be provided for adjusting the endwise position of the arbor 28 and it is for this purpose that the set screws 39 are provided in conjunction with the elongated slots 40. The manner in which the adjustment is made will be described presently.

For mounting the sanding drums 11-11 mounting sleeves 44-44 are provided at each end of the arbor 28.

They are nonrotatably secured thereon by haivng a press fit therewith. At their inner ends annular flanges 45-45 are welded as indicated at 46. Thus the annular flanges 4545 rotate with the mounting sleeves 44-44 which rotate with the arbor 28. One of the mounting sleeves 44 is provided with a right hand thread 47 and a correspondingly threaded nut 48 serves to clamp the respective floor if) sanding drum 11 in place against the respective annular flange 45. In like mannerthe other mounting sleeve 44 has a left hand thread 49 on which a correspondingly threaded nut d is mounted for clamping its floor sanding drum II against the respective annular flange 45.

The manner in which the various parts are assembled on the arbor is important. First the driven bevel gear 27 is slid over one end of the arbor 28 and against an annular shoulder 51, FIG. 4, with the arrangement being such that it has a press fit. In addition, as pointed out, a socket set screw can be employed for further securing the driven bevel gear 27 in position so that it rotates with the arbor 28. Next the antifriction bearing assemblies 3232 are mounted on the respective ends of the arbor 28. The left bearing assembly 32, as viewed in FIG. 2, is slid over the respective end of the arbor 23 until its inner race 37 engages a shoulder, similar to the shoulder 51. The right bearing assembly 32 is positioned, as shown in FIG. 4, with the inner race 38 spaced slightly from the juxtaposed end of the driven bevel gear 27. Finally, the mounting sleeves 44-44 are applied with a press fit to the respective ends of the arbor 28 with the arrangement being such that there is spacing, as shown in FIG. 4, between the inner end of the sleeve 44 and the juxtaposed end of the inner race 38.

One of the split snap rings 35 is removed and the arbor 23 assembled in the manner described is threaded through the bearing openings 29 in the ends of the arbor housing 12. This is permitted since the diameter of the annular flanges 45 is less than the diameter of the bearing openings 29 as indicated at 39. For example, the arbor 28, assembled as described, can be inserted through the right bearing opening 29, as viewed in FIG. 4, with the drive shaft 25 and drive bevel gear 26 withdrawn until the split snap ring 35 engages the end of the arbor housing 12 as here shown. This will position the groove for the other bearing assembly 32 in such position that its snap ring 35 can be applied. In order to make certain that this is the case, the left bearing assembly 32 can be adjusted slightly along the arbor 2 8.

Next the drive shaft 25 and drive bevel gear 26 are inserted in the upper end of the arbor housing 12 by mounting the latter on the underside of the platform 13. It will be apparent that the endwise position of the arbor 28 can be adjusted to provide the necessary meshing engagement between the teeth of the bevel gears 26 and 27 so that the noise incident to their operation is reduced to a minimum by adjusting the endwise position of the arbor 23 with respect to the inner races 38 of the bearing assemblies 3Z'32. When the proper adjustment is effected, the socket set screws 39 are tightened to bear against the respective flat bottom surfaces 41 of the elongated slots 40. It will be understood that, as wear takes place, further similar adjustments can be made in order to maintain the proper driving relationship between the teeth of the bevel gears 26 and 27.

What is claimed as new is:

1. In floor sanding apparatus and the like in which a motor drives a vertical shaft terminating at its lower end in a drive bevel gear, in combination, an arbor housing into which said drive bevel gear projects and having cylindrical bearing mounting openings at its ends, an arbor extending through said bearing openings and having fast thereon intermediate its ends a driven bevel gear whose teeth mesh with the teeth of said drive bevel gear, said arbor being adapted to receive at each end a sanding drum, annular flange means spaced from and fast on each end of said arbor and the respective end of said arbor housing against which the respective sanding drum is clamped for rotation with said arbor on rotation thereof by said vertical shaft; a bearing assembly at each end of I said arbor housing including an inner race adjustable along said arbor to vary the degree of meshing engagement between said bevel gears, an outer race removably mounted in the respective bearing mounting opening, and antifriction bearing means between said races; means preventing relative movement between each outer race and the respective end of said arbor housing,,and means preventing relative movement between each inner race and said arbor in the adjusted position thereof with said bevel gears in meshing engagement as aforesaid. V I j 2. In floor sanding apparatus and the like in which a motor drives a vertical shaft terminating at its lower end in a drive bevel gear, in combination, an arbor housing into which said drive bevel gear projects and having cylindrical bearing mounting openings at its ends, an arbor extending through said bearing openings and having fast thereon intermediate its ends a driven bevel gear whose teeth mesh with the teeth of said drive bevel gear, said arbor being adapted to receive at each end a sanding drum, annular flange means spaced from and fast on each end of said arbor and the respective end of said arbor housing against which the respective sanding drum is clamped for rotation with said arbor on rotation thereof by said vertical shaft; a bearing assembly at each end of said arbor housing including an inner race adjustable along said arbor to vary the degree of meshing engagement between said bevel gears, an outer race removably mounted in the respective bearing mounting opening, and antifriction bearing means between said races; the outside diameter of said driven bevel gear being less than the diameter of the adjacent bearing opening whereby said arbor with said driven bevel gear assembled thereon can be inserted or removed through said adjacent bearing opening, means preventing relative movement between each outer race and the respective end of saidarbor housing, and means preventing relative movement between each inner race and said arbor in the adjusted position thereof with said bevel gears in meshing engagement as aforesaid.

3. In floor sanding apparatus and the like in which a motor drives a vertical shaft terminating at its lower end in a drive bevel gear, in combination, an arbor housing into which said drive bevel gear projects and having cylindrical bearing mounting openings at its ends, an arbor extending through said bearing openings and having fast thereon intermediate its ends a driven bevel gear whose teeth mesh with the teeth of said drive bevel gear, said arbor being adapted to receive at each end a sanding drum, annular flange means spaced from and fast on each end of said arbor and the respective end of said arbor housing against which the respective sanding drum is clamped for rotation with said arbor on rotation thereof by said vertical shaft; a bearing assembly at each end of said arbor housing including an inner race adjustable along said arbor to vary the degree of meshing engagement between said bevel gears, an outer race removably mounted in the respective bearing mounting opening, antifriction heating means between'said races, and an annular snap ring extending radially. from said outer race and bearing against the respective 'end face of said arbor housing; the outside diameter of said driven bevel gear being less than the diameter of the adjacent bearing opening whereby said arbor with said driven bevel gear assembled thereon can be inserted or removed through said adjacent bearing or opening, means preventing relative movement between each outer race and the respective end of said arbor housing, and means preventing relative movement between each inner race and said arbor in the adjusted position thereof with said bevel gears in meshing engagement as aforesaid.

4. In floor sanding apparatus and the like in which a motor drives a vertical shaft terminating at its lower end in a drive bevel gear, in combination, an arbor housing into which said drive bevel gear projects and having cylindrical bearing mounting openings'at its ends, an arbor extending through said bearing openings and having fast thereon intermediate its ends a driven bevel gear whose teeth mesh with the teeth of said drive bevel gear, said arbor being adapted to receive at each end a sanding drum, annular flange means spaced from and fast on each E d end of saidtarbor and the respective end of said arbo housing against which therespective'sanding drum is clamped for rotation with said arboron rotation thereof by said vertical shaft, the diameter of each radial flange means being less than the diameter of said bearing openings; a bearing assembly at each end of said arbor housing including an inner race adjustable along said arbor to vary the degree of meshing engagement between said bevel gears, an outer race removably mounted in the respective bearing mounting opening, and antifriction hearing means between 'said races; the outside diameter of said driven bevel gear being less than the diameter of said bearing openings whereby said arbor with said driven bevel gear, said flange means and said hearing as-' semblies assembled onsaid arbor can be inserted or removed through said bearing openings, means preventing relative movement between each outer race and the respective end of said arbor housing, and means preventing relative movement between each inner race and said 7 motor drives a vertical shaft terminating at its lower end in a drive bevel gear, in combination, an arbor housing into which said drive bevel gear projects and having cylindrical bearing mounting openings at its ends, an arbor extending through said bearing openings and having fast thereon intermediate its ends a driven bevel gear Whose teeth mesh with the teeth of said drive bevel gear, said arbor being adapted to receive at each end a sanding drum, annular flange means spaced from and fast on each end of said arbor and the respective end of said arbor housing against which the respective sanding drum is clamped for rotation with said arbor on rotation thereof by said vertical shaft, the diameter of each radial flange means being less than the diameter of said bearing openings; a bearing assembly at each end of said arbor housin including an inner race adjustable along said arbor to vary the degree of meshing engagement between said bevel gears, an outer race removably mounted in the respective bearing mounting opening, and antifriction bearing means between said races; the outside diameter of said drivenbevel gear being less than the diameter of said bearing openings whereby said arbor with said driven bevel gear, said flange means and said bearing assemblies assembled on said arbor can be inserted or removed through said bearing openings, means preventing relative movement between each outer race and the respective end of said arbor housing, each inner race overlying a slot extending lengthwise of said arbor, and set screw means threaded through the overlying portion of each inner race and engaging said arbor at the bottom of the respective slot to hold said arbor in adjusted position with said bevel gears in meshing engagement as aforesaid.

References Cited in the, file of this patent UNITED STATES PATENTS 907,058 Kraemer et a1 Dec. 15, 1908 1,198,026 Hampton Sept. 12, 1916 1,900,331 Clark Mar. 7, 1933 1,947,136 Moorhead Feb. 13, 1934 2,230,899 McGrath Feb. 4, 1941 2,891,412 Jackson June 23, 1959 

1. IN FLOOR SANDING APPARATUS AND THE LIKE IN WHICH A MOTOR DRIVES A VERTICAL SHAFT TERMINATING AT ITS LOWER END IN A DRIVE BEVEL GEAR, IN COMBINATION, AN ARBOR HOUSING INTO WHICH SAID DRIVE BEVEL GEAR PROJECTS AND HAVING CYLINDRICAL BEARING MOUNTING OPENINGS AT ITS ENDS, AN ARBOR EXTENDING THROUGH SAID BEARING OPENINGS AND HAVING FAST THEREON INTERMEDIATE ITS ENDS A DRIVEN BEVEL GEAR WHOSE TEETH MESH WITH THE TEETH OF SAID DRIVE BEVEL GEAR, SAID ARBOR BEING ADAPTED TO RECEIVE AT EACH END A SANDING DRUM, ANNULAR FLANGE MEANS SPACED FROM AND FAST ON EACH END OF SAID ARBOR AND THE RESPECTIVE END OF SAID ARBOR HOUSING AGAINST WHICH THE RESPECTIVE SANDING DRUM IN CLAMPED FOR ROTATION WITH SAID ARBOR ON ROTATION THEREOF BY SAID VERTICAL SHAFT; A BEARING ASSEMBLY AT EACH END OF SAID ARBOR HOUSING INCLUDING AN INNER RACE ADJUSTABLE ALONG SAID ARBOR TO VARY THE DEGREE OF MESHING ENGAGEMENT BETWEEN SAID BEVEL GEARS, AN OUTER RACE REMOVABLY MOUNTED IN THE RESPECTIVE BEARING MOUNTING OPENING, AND ANTIFRICTION BEARING MEANS BETWEEN SAID RACES; MEANS PREVENTING RELATIVE MOVEMENT BETWEEN EACH OUTER RACE AND THE RESPECTIVE END OF SAID ARBOR HOUSING, AND MEANS PREVENTING RELATIVE MOVEMENT BETWEEN EACH INNER RACE AND SAID ARBOR IN THE ADJUSTED POSITION THEREOF WITH SAID BEVEL GEARS IN MESHING ENGAGEMENT AS AFORESAID. 